OR30-1 Cloning, Sequencing, and Characterization of Aromatase Interacting Partner in Breast (AIPB). A New Protein Regulating Estradiol Synthesis

Breast cancer is the most common invasive cancer in females worldwide and accounts for 16% of all female cancers, 22.9% of invasive cancers in women, and 18.2% of all cancer-related deaths worldwide. About 80% of these cancers, once established, depend on available estrogens (i.e., estradiol) to grow. The production of estrogens occurs via a catalytic process governed by the enzyme Aromatase. This process occurs primarily in the ovaries in pre-menopause, while in post-menopause, this occurs in peripheral tissues, including the breast. In patients whose cancers have specific hormone receptors, such as Estrogen Receptor positive (ER+), Progesterone Receptor positive (PR+), and Human Epidermal Growth Factor 2 Receptor positive (HER2+), these tumors can continue receiving nutrients and signals to grow, which provides targets for therapy. Although many of the currently available drugs for breast cancer seek to suppress this process and thus reduce available estrogens, they have numerous harmful side effects and have high rates of therapy failure due to the development of resistance. Therefore, new therapies and targets for this devastating disease are needed. We observed that breast tumors had increased estrogen production in postmenopausal women, leading us to question the cause of this increase. Further, the complete mechanism of aromatase action and the possibility of targetable cofactors remained previously unknown. Thus, we set out to identify the mechanism of Aromatase action to provide prognostic and therapeutic insight into this distressing disease. As Aromatase is an endoplasmic reticulum (ER) resident protein, we purified ER fractions from breast tissues, separated through 1D, and then each ten kDa fractions were further separated and analyzed through Mass-spectrometry to determine the cofactors associated with aromatase activity. We observed an 11 mer peptide LEVVVDQPMER, which on cloning resulted in a 207 amino acid protein not present in the database. This previously undiscovered protein is colocalized with Aromatase in the ER. We saw that knocking down its expression by siRNA in wild-type breast cells (MCF-12A) or tumorigenic MCF-7 or T47-D cells increased estradiol synthesis significantly without affecting aromatase expression. Further biochemical experiments showed that Aromatase and the 207 amino acid protein interacted directly without affecting the expression of other ER-resident proteins. Additionally, our experiments showed that the new protein is not hormonally stimulated or transcriptionally inhibited and thus, regulates the aromatase catalytic activity of estradiol synthesis. Therefore, we have termed this new protein "Aromatase Interacting Partner in Breast" (AIPB).

Presentation: Tuesday, June 14, 2022 9:45 a.m. - 10:00 a.m.

ODP539 AIPB is a Biomarker for ER+/PR+/Her2- Breast Cancers

Aromatase, the rate-limiting enzyme in estrogen synthesis, is expressed in the ovaries of premenopausal, the placentas of pregnant women, and adipose tissue and skin cells in postmenopausal women, although to a lesser extent than in the ovaries. The direct mechanism of controlling breast cancer is to reduce estrogen synthesis by interfering with its production, via ovarian ablation in premenopausal women and use of aromatase inhibitors or inactivators. However, the latter results in drug resistance, making them ineffective for future treatment. In our laboratory, we identified a 22-kDa protein from human breast tissue, Aromatase Interacting Partner in Breast (AIPB), that interacts with aromatase. Western Blotting of the unaffected (nontumorigenic MCF-12A) and tumorigenic (MCF-7 ER+/PR+/Her2-) breast tissues as well as PCR amplification with the AIPB specific primers of the nontumorigenic and tumorigenic cells showed AIPB expression is maximum with the unaffected breast tissue but reduced in ER+/PR+/Her2- tumors. To confirm AIPB's regulatory role, we developed a conditional expression of AIPB by stably selecting with puromycin from MCF-7 cells and thus regulating AIPB expression under a tetracycline promoter. On addition of doxycycline followed by PCR amplification, the AIPB expression was enormously higher than the uninduced cells under identical condition. The estrogenic effect of the stable cells was reduced significantly compared to MCF-7 cells. In summary, our preliminary results suggest AIPB to be a potential biomarker with a potential for cell therapy-mediated decrease of estradiol in ER+/PR+/Her2- tumorigenic breast tissues.

Presentation: No date and time listed

Preoperative Predictive Factors of Positive Margin Status After Breast Conserving Therapy (BCT) with Intraoperative Radiation Therapy (IORT): A Retrospective Study of 400 Patients

INTRODUCTION

Single-fraction intraoperative radiation therapy (IORT) has emerged as a therapeutic option in patients undergoing breast conserving therapy (BCT) for early stage breast cancer, often eliminating the need for postoperative external beam radiation therapy. However, if a positive margin is encountered after BCT, the patient will ultimately require external beam radiation therapy. The purpose of this study was to identify preoperative factors from patient demographics, preoperative workup, or biopsy results that may be predictive of postoperative margin status.

MATERIALS AND METHODS

A retrospective chart review was performed on 396 patients who underwent BCT with IORT. Logistic regression models were utilized for statistical analysis.

RESULTS

The majority of studied variables were similar; however, differences were noted for high-grade tumors, in situ status, and progesterone receptor-negative (PR^-) tumors. Grade 3 tumors were significantly associated with positive margin status when compared with Grade 1 (odds ratio, 2.30; P = .036). PR^- status tumors were found to be approximately 2 times more likely to have a positive margin (P = .028). Patients with in situ (stage 0) status tumors were 1.986 times more likely to have positive margins when compared with those with an invasive tumor (P = .030).

CONCLUSIONS

Higher grade PR^- tumors are at increased risk of having a positive margin, which should be taken into consideration when considering treatment with IORT.

Biodynamic response prediction in breast cancer patients receiving neoadjuvant chemotherapy

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Background: Biodynamic signatures (temporal patterns of microscopic motion within a three-dimensional tumor explant) offer a phenomic biomarker that is highly predictive for therapeutic response. The purpose of this study is to evaluate predictive accuracy of a biodynamic drug response classifier in breast cancer patients receiving neoadjuvant chemotherapy (NAC). Methods: Consecutive breast cancer patients from 4 institutions were screened for enrollment in a prospective observational study (NCT03164863). Treatment-naïve needle biopsies were delivered to a central laboratory where biodynamic signatures were measured in living tumor fragments challenged by standard-of-care cytotoxins. Patients received NAC per institutional guidelines and were followed through surgical intervention. A four-point classifier was trained to predict pathologic complete response (CR) then prospectively validated. Results: Among patients completing neoadjuvant treatment and surgical intervention, 33% (24 of 72) achieved CR. The biodynamic classifier predicted CR with 96% sensitivity and 97% negative predictive value. Biodynamically “favored” (scoring ≥ 3) and “strongly favored” (scoring 4) regimens produced CR at rates of 56% (23 of 41) and 73% (19 of 26), respectively. Only 3% of patients (1 of 31) achieved CR from regimens scoring 1 or 2. Area under the receiver operating curve (AUC) was 87% (95% CI: 75% to 93%, p < .0001), with similar performance across all subtypes and therapy cohorts (range: 84% to 89%). Performance of the classifier on training and validation patients was statistically equivalent. Conclusions: Biodynamic scoring accurately predicts response in breast cancer patients receiving NAC and holds promise to substantially improve management of these patients. [Table: see text]

Abstract P3-11-17: A novel biodynamic imaging assay predicts success or failure of neoadjuvant chemotherapy in breast cancer patients

Background: Use of neoadjuvant chemotherapy (NAC) in breast cancer patients has increased significantly over the past decade. The clinical benefits of NAC, including potential to downstage disease, facilitation of breast conserving surgery and use of pathologic response as a prognostic marker, are well established. However, with multiple regimens approved and recommended for NAC, choosing the optimal therapy for individual patients remains a challenge. Biodynamic imaging (BI), a novel technology that captures cellular motility in living tissue via Doppler spectroscopy, could be used ex-vivo to prospectively evaluate the efficacy of systemic therapies in patient tumor samples prior to treatment. This study aimed to determine whether BI could accurately predict likelihood of response to NAC in breast cancer patients.

Methods: Fresh core biopsies were obtained from 84 patients prospectively enrolled in an IRB-approved clinical trial at 5 institutions between 1/5/17 and 8/3/2018. Patient tumor tissue was collected at time of routine diagnostic biopsy and sent to a central laboratory where it was divided into intact tumor fragments measuring approximately 1mm in diameter. Fragments were placed into 96 well plates and imaged using the BI assay (Onco4D™), while being challenged by various cytotoxic agents for up to 20 hours. Cellular characteristics and motility signatures were evaluated and compared to pathologic NAC response established upon surgical resection (mastectomy or lumpectomy).

Results: At the time of this analysis, centrally-confirmed pathologic response data were available for 17 patients treated with doxorubicin/cyclophosphamide + taxane (AC). Pathologic outcomes are pending for an additional 8 AC patients. The remainder of the 84 patients initially enrolled in the study either did not receive NAC (n=10), have not yet selected a course of therapy (n=12), or received NAC regimens other than AC (n=37). Of the 17 currently evaluable AC-treated patients, 4 had triple negative (TN) disease, 12 were hormone receptor positive, and 1 hormone receptor negative patient showed equivocal HER2 results. Two of the TN patients were known to harbor pathogenic BRCA1 mutations and received carboplatin in addition to AC. Seven of 17 patients (40%) displayed resistance to AC (2 with progressive and 5 with stable disease) while 10 experienced objective response (8 partial and 2 complete response). A multilinear regression model using 10 BI markers accurately classified 16 of 17 patients (94%) while producing 1 false prediction of partial response for a patient with stable disease clinically (R-squared=0.9994, p&lt;.0001). The positive predictive and negative predictive values of BI to AC response were 100% and 91%, respectively.

Table 1.Performance Characteristics  Clinical   OutcomeResponseNon-ResponseTotalClassifierResponse10111 Non-Response066 Total10717

Conclusion: BI was able to accurately predict patient response to neoadjuvant AC, demonstrating the potential for the platform to support personalized patient therapy. This clinical trial is ongoing and will report out results for TC (docetaxel/cyclophosphamide), TCHP (docetaxel/carboplatin/trastuzumab + pertuzumab), and additional AC patients as outcome data are accrued.

Citation Format: Whitacre E, Manahan E, Burak W, Morgan T, An R, Loesch D. A novel biodynamic imaging assay predicts success or failure of neoadjuvant chemotherapy in breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-11-17.

Phase II trial of neoadjuvant chemotherapy with docetaxel followed by epirubicin in stage II/III breast cancer

PURPOSE

In most neoadjuvant chemotherapy regimens, the taxane is administered either in combination with an anthracycline or after an anthracycline-containing regimen. We sought to test the feasibility, safety, and determine the pathological complete response (pCR) rate of administering docetaxel first followed by epirubicin as neoadjuvant chemotherapy in women with clinical stage II, III breast cancer.

PATIENTS AND METHODS

Twenty-five women with newly diagnosed clinical stage IIB (n = 10), IIIA (n = 5), or IIIB (n = 10) received 3 cycles of docetaxel 100 mg/M2 intravenously (IV) every 3 weeks followed by 3 cycles of epirubicin 100 mg/M2 IV every 3 weeks. pCR was defined as the absence of invasive cancer in the breast at definitive surgery.

RESULTS

The median primary tumor size was 6 cm (range 1-12 cm), and 13 (52%) women had clinically palpable axillary lymph nodes. Patients received 149 of the 150 planned cycles of docetaxel and epirubicin without treatment delays, and only 3 (12%) patients had a dose reduction of docetaxel. Seven (28%) patients experienced febrile neutropenia, and 9 (36%) patients had grade 3 non-hematological toxicities with diarrhea being the most frequent in 3 (12%) patients. Six (24%) patients had pCR in the breast. Analysis of pre- and post-docetaxel biopsies from a subset of patients documented taxane-induced activation of mitogen-activated and stress-activated protein kinase pathways.

CONCLUSION

Neoadjuvant docetaxel followed by epirubicin is well tolerated and active in breast cancer. To our knowledge, this is first description of docetaxel-induced activation of mitogen-activated and stress-activated protein kinase pathways in human breast cancer.

[Diagnosis of diabetic autonomic neuropathy in young patients with diabetes mellitus type 1]

Autonomic neuropathy, particularly cardiovascular autonomic neuropathy (CAN) is one of the complications of the diabetes mellitus both types. It leads to life comfort's declination but may also be the direct cause of death in diabetes mellitus patients. It seems that degree of metabolic control and duration of the disease is connected with prevalence and severity of CAN. The aim of our study was to assess cardiac autonomic function in young subjects suffered from insulin-dependent diabetes mellitus (IDDM) with relatively short duration time of the disease. We subdivided 25 (m-12, f-13) IDDM patients aged from 18 to 30 years: mean--26 +/- 38 years, with duration time of the disease up to 10 years, normotensive and without nephropathy and retinopathy. We created 25 healthy volunteers control group with similar age and sex. In all selected subjects full Ewing's battery tests were performed as well as the spectral analysis of power heart rate variability (HRV) was assessed with Finapress device (Ohmeda 2300) and automatically computed with special software. HRV in total spectrum power TP from 0.001-0.5 Hz, high frequency (HF) band from 0.15-0.3 Hz, low frequency (LF) band from 0.03-0.15 Hz and LF/HF ratio were examined both in supine and tilt. All assessed spectral values were significantly lower in IDDM patients then these in controls whereas LF/HF were respectively higher. Valsalva tests and deep breathing HR response tests were significantly differed among groups but within normal limits. We concluded that when spectral analyse was performed, in young IDDM patients with short duration time of the disease, impairment of cardiac autonomic function was observed.

The role of aldose reductase gene in the susceptibility to diabetic nephropathy in Type II (non-insulin-dependent) diabetes mellitus

The dinucleotide repeat polymorphism (5'-ALR2) in the promoter region of the aldose reductase gene on chromosome 7q35 has been implicated in the development of diabetic nephropathy in Type I (insulin-dependent) diabetes mellitus, and markers flanking the aldose reductase locus have given evidence suggestive of a linkage between diabetic nephropathy and Type II (non-insulin-dependent) diabetes mellitus in Pima Indians. To examine whether the 5'-ALR2 polymorphism in the aldose reductase gene is involved in the development of diabetic nephropathy in Caucasians with Type II diabetes, we carried out a large association study. Patients with Type II diabetes from one outpatient clinic were screened for diabetic nephropathy and divided into three groups according to the degree of this disease: 179 patients with normoalbuminuria, 225 patients with microalbuminuria and 70 patients with proteinuria. Patients with normoalbuminuria were included in the study only if they had had Type II diabetes for 10 or more years. DNA from all patients was genotyped for the 5'-ALR2 polymorphism using a previously established polymerase chain reaction protocol. The frequency of the putative risk allele Z-2 was 34.6%, 34.2% and 33.6% in the normoalbuminuria, microalbuminuria and proteinuria groups, respectively. Similarly no difference among groups was found for the frequency of the putative protective allele Z + 2. In conclusion, the results of our association study in Caucasian patients with Type II diabetes do not support the hypothesis that the 5'-ALR2 polymorphism in the aldose reductase gene contributes to susceptibility to diabetic nephropathy.

[Changes in levels of atrial natriuretic peptide (ANP) in patients with chronic renal failure during physical exertion]

Many endocrine abnormalities were reported in patients with chronic renal failure (CRF), including elevated ANP, but little is known on ANP vaso-regulatory effects during exercise. This study is aimed to find whether plasma ANP rises during exercise in patients with CRF, as it does in normal subjects, and whether there is a difference between this response in both those groups. 36 subjects were studied, divided into three groups: I--CRF patients treated conservatively (nondialyzed), II--CRF patients, dialyzed, III--healthy subjects. Plasma ANP was measured at rest and then immediately after submaximal treadmill work load according to modified Bruce protocol with continuous ecg and blood pressure monitoring. In the CRF nondialyzed patients the metabolic equivalent (MET) was significantly lower than in the other groups. The myocardial oxygen consumption, estimated as double product quotient, was the lowest in the nondialyzed CRF patients. A significant increase of the plasma ANP was seen in all subjects studied, significantly higher in the CRF patients than in the control healthy subjects. No correlations were found between the plasma ANP level and other measured parameters.

[Effect of physical exertion on levels of vasopressin (AVP) and plasma renin activity in patients with chronic kidney failure]

In uraemic subjects many endocrine abnormalities were observed. Plasma vasopressin (AVP) levels and plasma renin activity (PRA) were significantly higher than in normals, but little is known about their vasoregulatory effects during exercise. The aim of our study was to find the answer on the following question: 1.were any significant changes in AVP and PRA levels during exercise in uremic patients and in normals occurred, 2.were any hormonal profile differences between nonhaemodialysed and haemodialysed patients existed, 3.does the correlation between blood pressure changes and AVP and PRA exist. Plasma AVP and PRA levels were measured in 12 uraemic non-haemodialysed subjects, in 12 uraemic haemodialysed subjects and in 12 healthy subjects. In all groups AVP and PRA were examined two times--first in normal conditions (rest) and second time after submaximal work load during ECG exercise test with continuous blood pressure monitoring. In nonhaemodialysed subjects METs value were significantly lower than in other groups. Mean increase of mean blood pressure was comparable between observed groups. We didn't find any significant correlation between changes in plasma AVP and PRA level and other measured parameters.

CONCLUSIONS

1. Exercise test induced qualitatively the same but quantitatively different changes in plasma AVP and PRA concentrations in uraemic and healthy subjects. 2.No significant differences in basal conditions as well as after exercise in plasma AVP and PRA between nonhaemodialysed and haemodialysed patients were observed. 3.No significant correlation between blood pressure and hormonal changes was found.

[Levels of beta-2-microglobulin (B2MG) in blood serum of patients during the early phase after kidney transplantation]

In uremic subjects serum B2MG levels was significantly higher than in normals. In kidney transplant patients (KTP) serum B2MG levels was 3-4 times higher than in normals. Elevated serum B2MG levels in KTP seems to depend not only on the kind of immunosuppressive therapy but also on other factors. In the present study we aimed to asses serum B2MG levels immediately after KT. B2MG were assessed in 25 uremic patients at the early phase after KT and in 12 controls (patients immediately after cholecystectomy). All uremic patients were divided on two groups: group I-patients with immediately graft function after transplantation (12 patients) and group II--patients with acute failure of the transplanted kidney (13 patients). In all examined subjects immediately before and 1, 2, 3, 4, 5, 10, 15, 20, 25, and 30 days after transplantation serum B2MG levels were assessed using RIA methods. In group I we observed gradually decline of B2MG concentrations parallel with creatinine after KT while in group II normalization of B2MG and creatinine levels were delayed (approximate 10 days). The significant positive correlation was found between plasma B2MG and creatinine levels in all examined patients. We concluded: 1. In all examined groups the tendency to normalization of B2MG levels after KT was observed. 2. Acute failure transplanted kidney delayed normalization of B2MG concentrations. 3. Normalization of B2MG levels was preferentially dependent on the graft function.

[Comparison of beta-2-agonist and beclomethasone effects on potassium levels, heart action and pulmonary ventilation parameters in patients with chronic asthmatic bronchitis]

The main goal of asthma treatment has usually been to maintain normal air potency with bronchodilators. A prompt improvement in physiologic measures of expiratory flow can be observed after administration beta-2-agonists or steroids. The present study aimed to assay the influence of fenoterol or beclomethasone therapy on the pulmonary ventilation (VC, FEV1, FEV1%), the heart action (heart rate, QT interval, 24 hours ECG) and the potassium balance in examined group. 20 patients with chronic asthmatic bronchitis were divided on two group (A and B). Group A consisted 10 subjects and patients were treated with fenoterol, the second group (Group B) consisted 10 subjects too, and patients were treated with beclomethasone. After five days treatment in all subjects an increase VC, FEV1 and FEV1% were observed. In group A (inhalation of fenoterol) we observed: 1--the significant increase of heart rate, QT interval, and frequency of cardiac arrhythmias and 2--significant decrease plasma potassium levels. In group B we didn't observed a significant changes in heart function and potassium levels. We concluded that nebulization of fenoterol, even in low doses, required control of the plasma potassium concentration and the evaluation of the heart action.

[Long-term oxygen therapy of chronic pulmonary heart disease]

Pulmonary artery pressure was measured in 70 patients with chronic bronchitis. Those with pulmonary hypertension underwent two hours oxygen therapy (flow 10-12 l/min). Those in whom a decrease of pulmonary artery pressure was observed were qualified for long term oxygen therapy (LTOT). In 32 patients which were qualified for LTOT, after a two week period of 18 hour per day oxygen therapy a decrease of systolic pulmonary arterial pressure from 336.1 mm Hg to 30.9 mm Hg and a decrease of mean pulmonary artery pressure from 25.9 to 23.2 mm Hg was observed.

[Selected parameters of the immune system in coal miners with pneumoconiosis]

The study was carried out in a group of 84 men divided in three groups: I--41 miners with simple pneumoconiosis, II--25 miners exposed to coal dust for the same period, and III--28 healthy persons of similar age (control group). All the persons were studied for absolute and proportional values of T and B lymphocytes, also subpopulation of TH helper lymphocytes and TS suppressor lymphocytes, a lymphocyte index (TH/TS) was determined. Besides, the concentration of serous immunoglobulins IgG, IgA and IgM was determined. The author showed a statistically significant decrease in the number of TS suppressor lymphocytes in the group of patients with pneumoconiosis and at the same time an increase in the lymphocyte index in comparison with the other groups. Besides, the author also found a significant decrease in the total amount of T lymphocytes in the same group and at the same time an increase in the concentrations of serous immunoglobulins IgG, IgA. The changes observed in the immunological system in patients with pneumoconiosis may lie at the bottom of the pathogenesis of fibrosis .